The Tx hang logic has been known to detect false hangs when
the device is receiving pause frames or has delayed processing
for some other reason.
This patch makes the logic more robust and resolves these
known issues. The old logic checked to see if the device
was paused by querying the HW then the hang logic was
aborted if the device was currently paused. This check was
racy because the device could have been in the pause state
any time up to this check. The other operation of the
hang logic is to verify the Tx ring is still advancing
the old logic checked the EOP timestamp. This is not
sufficient to determine the ring is not advancing but
only infers that it may be moving slowly.
Here we add logic to track the number of completed Tx
descriptors and use the adapter stats to check if any
pause frames have been received since the previous Tx
hang check. This way we avoid racing with the HW
register and do not detect false hangs if the ring is
advancing slowly.
This patch is primarily the work of Jesse Brandeburg. I
clean it up some and fixed the PFC checking.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change resolves some null function pointer accesses on 82598 when a
multi-speed fiber module is inserted into the adapter.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
The q_vector back pointer was not being set in the rings so it would not
have been possible to determine the parent q_vector of the ring.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change cleans up some of the items in ixgbe_map_rings_to_vectors.
Specifically it merges the two for loops and drops the unnecessary vectors
parameter.
It also moves the vector names into the q_vectors themselves.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change is meant to improve the stack utilization and simplify the math
used in ixgbe_set_itr_msix.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
There are a number of places where we use the variable j to contain the
register index of the ring. Instead of using such a non-descriptive
variable name it is better that we name it reg_idx so that it is clear what
the variable contains.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change is just to cleanup some confusing logic in ixgbe_cache_ring_rss
which can be simplified by adding a conditional with return to the start of
the call.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change address a few whitespace issues in DCB #ifdefs, adds a comment
calling out the DCB specific registers, and nests an if statement inline
with a number of if statements related to flow control.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change adds support for certain 82599 based Mezzanine adapters.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change makes it so that we always disable SCTP regardless of mac type
since we shouldn't need to check mac type before disabling a feature that
isn't supported on a given piece of hardware.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change replaces a number of if/elseif/else statements with switch
statements to support the addition of future devices to the ixgbe driver.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change cleans up the use of rsc_count and changes it to a boolean since
the actual numerical value is used nowhere in the Rx cleanup path. I am
also moving the skb count into the RSC_CB path since it is much easier to
track it there than when it is passed as a parameter to various function
calls.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change cleans up the ixgbe_atr filter setup function so that it uses
fewer items from the stack. Since the code is only applicable to IPv4 w/
TCP it makes sense to just use the pointers based on the headers themselves
instead of copying them to temp variables and then writing those to the
filters.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
The code for ixgbe_clean_rx_irq was much more tangled up than it needed to
be in terms of logic statements and unused variables. This change
untangles much of that and drops several unused variables such as cleaned
which was being returned but never checked.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This changes the numbering scheme slightly. Previously the ordering was
coming out like this:
Rx-2
Rx-1
Rx-0
TxRx-0
Which would drop two queues on CPU 0. This change makes it so that the
ordering is like this:
Rx-3
Rx-2
Rx-1
TxRx-0
This means that each CPU will have it's own Rx queue, and only CPU 0 will
have the Tx queue.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
The code as it existed could re-arm the queues when it was requesting a HW
reset due to a TX hang. Instead of doing that this change makes it so that
we will just exit if the hardware is believed to be hung.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
RSC will flush its descriptors every time the interrupt throttle timer
expires. In addition there are known issues with RSC when the rx-usecs
value is set too low. As such we are forced to clear the RSC_ENABLED bit
and reset the adapter when the rx-usecs value is set too low.
However we do not need to clear the NETIF_F_LRO flag because it is used to
indicate that the user wants to leave the LRO feature enabled, and in fact
with this change we will now re-enable RSC as soon as the rx-usecs value is
increased and the flag is still set.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change makes it so that we perform link setup with interrupts
disabled. If the SFP has not been detected previously we will schedule the
SFP detection task to run in order to detect link. By doing this we avoid
the possibility of interrupts firing in the middle of our link setup during
ixgbe_up_complete.
In addition this change makes it so that the multi-speed fiber setup and SFP
setup are not mutually exclusive. The addresses issues seen in which a
link would only come up at 1G on some multi-speed fiber modules.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change adds a set of state flags to the rings that allow them to
independently function allowing for features like RSC, packet split, and
TX hang detection to be done per ring instead of for the entire device.
This is accomplished by re-purposing the flow director reinit_state member
and making it a global state instead since a long for a single bit flag is
a bit wasteful.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This is the start of work to sort out what belongs in the rings and what
belongs in the q_vector. Items like the CPU variable for make much more
sense in the q_vector since the CPU is a per-interrupt thing rather than a
per ring thing.
I also added a back-pointer from the ring to the q_vector.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change moves an adapter pointer into the private portion of the
pci_dev instead of a pointer to the netdev. The reason for this change is
because in most cases we just want the adapter anyway. In addition as we
start moving toward multiple netdevs per port we may want to move the
adapter pointer out of the netdevs entirely.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Missed some code that was left floating around in the DCB configuration
for the TXDCTL register. As a result the register was being messed with in
two different spots when we only needed to do the change once.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
The main reason for this change is to keep the suspend/resume logic matched
up. The clear_interrupt_scheme function will disable MSI-X which will
effect the PCIe configuration space. Therefore we will want to do it before
we save state to avoid having the interrupt state restored by
pci_restore_state, and then trying to re-enable MSI/MSI-X interrupts via
ixgbe_setup_interrupt_scheme.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change places a netdev pointer directly into the ring structure. This
way we can avoid having to determine which netdev we are supposed to be
using and can just access the one on the ring directly.
As a result of this change further collapse of the code is possible by
dropping the adapter from ixgbe_alloc_rx_buffers, and the netdev pointer
from ixgbe_xmit_frame_ring_adv and ixgbe_maybe_stop_tx.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change moved some of the RX and TX stats into separate structures and
them placed those structures in a union in order to help reduce the size of
the ring structure.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change is meant to simplify DMA map/unmap by providing a device
pointer. As a result the adapter pointer can be dropped from many of
the calls.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change drops ring->head since it is not used in any hot-path and can
easily be determined using IXGBE_[RT]DH(ring->reg_idx).
It also changes ring->tail into a true pointer so we can avoid unnecessary
pointer math to find the location of the tail.
In addition I also dropped the setting of head and tail in
ixgbe_clean_[rx|tx]_ring. The only location that should be setting the head
and tail values is ixgbe_configure_[rx|tx]_ring and that is only while the
queue is disabled.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change re-orders alloc_rx_buffers to make better use of the packet
split enabled flag. The new setup should require less branching in the
code since now we are down to fewer if statements since we either are
handling packet split or aren't.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
This change simplifies the work being done by the TX interrupt handler and
pushes it into the tx_map call. This allows for fewer cache misses since
the TX cleanup now accesses almost none of the skb members.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
There is no need to reset the adapter when changing the Rx checksum
settings. Since the only change is a software flag we can disable it
without needing to reset the entire adapter.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
The maximum credits per traffic class only needs to be greater
then the TSO size for 82598 devices. The 82599 devices do not
have this requirement so only do this test for 82598 devices.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Currently the high and low water marks for PFC are being set
conservatively for jumbo frames. This means the RX buffers
are being underutilized in the default 1500 MTU. This patch
fixes this so that the water marks are set as described in
the data sheet considering the MTU size.
The equation used is,
RTT * 1.44 + MTU * 1.44 + MTU
Where RTT is the round trip time and MTU is the max frame size
in KB. To avoid floating point arithmetic FC_HIGH_WATER is
defined
((((RTT + MTU) * 144) + 99) / 100) + MTU
This changes how the hardware field fc.low_water and
fc.high_water are used. With this change they are no longer
storing the actual low water and high water markers but are
storing the required head room in the buffer. This simplifies
the logic and we do not need to account for the size of the
buffer when setting the thresholds.
Testing with iperf and 16 threads showed a slight uptick in
throughput over a single traffic class .1-.2Gbps and a reduction
in pause frames. Without the patch a 30 second run would show
~10-15 pause frames being transmitted with the patch ~2-5 are
seen. Test were run back to back with 82599.
Note RXPBSIZE is in KB and low and high water marks fields are
also in KB. However the FCRT* registers are 32B granularity and
right shifted 5 into the register,
(((rx_pbsize - water_mark) * 1024) / 32) << 5
is the most explicit conversion here we simplify
(rx_pbsize - water_mark) * 32 << 5 = (rx_pbsize - water_mark) << 10
This patch updates the PFC thresholds and legacy FC thresholds.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Update version string and copyright notice.
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Emil Tantilov <emil.s.tantilov@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
"cat /proc/net/dev" uses RCU protection only.
Its quite possible we call a driver get_stats() method while device is
dismantling and freeing its data structures.
So get_stats() methods must be very careful not accessing driver private
data without appropriate locking.
In ixgbe case, we access rx_ring pointers. These pointers are freed in
ixgbe_clear_interrupt_scheme() and set to NULL, this can trigger NULL
dereference in ixgbe_get_stats64()
A possible fix is to use RCU locking in ixgbe_get_stats64() and defer
rx_ring freeing after a grace period in ixgbe_clear_interrupt_scheme()
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Reported-by: Tantilov, Emil S <emil.s.tantilov@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
When operating in a mode that initiates communication and using
HT40 we should fail if we cannot use both primary and secondary
channels to initiate communication. Our current ht40 allowmap
only covers STA mode of operation, for beaconing modes we need
a check on the fly as the mode of operation is dynamic and
there other flags other than disable which we should read
to check if we can initiate communication.
Do not allow for initiating communication if our secondary HT40
channel has is either disabled, has a passive scan flag, a
no-ibss flag or is a radar channel. Userspace now has similar
checks but this is also needed in-kernel.
Reported-by: Jouni Malinen <jouni.malinen@atheros.com>
Cc: stable@kernel.org
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
AR9287 based PCI & USB devices are differed in eeprom start offset.
So set proper the offset for HTC devices to read nvram correctly.
Cc: stable@kernel.org
Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Treat new PIDs (0xA704, 0x1200) as AR7010 devices.
Cc: stable@kernel.org
Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Added new VID/PIDs into supported devices list
Cc: stable@kernel.org
Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Update pm_qos before removing it in deinit_device to prevent this
warning:
pm_qos_update_request() called for unknown object.
Signed-off-by: Vivek Natarajan <vnatarajan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
otherwise xfrm_lookup will fail to find correct policy
Signed-off-by: Ulrich Weber <uweber@astaro.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit 1e4e0767ec (Fix locking on fec_mpc52xx driver) assumed IRQ are
enabled when an IRQ handler is called.
It is not the case anymore (IRQF_DISABLED is deprecated), so we can use
regular spin_lock(), no need for spin_lock_irqsave().
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Jean-Michel Hautbois <jhautbois@gmail.com>
Cc: Asier Llano <a.llano@ziv.es>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>
Right now, fields in struct sock are not optimally ordered, because each
path (RX softirq, TX completion, RX user, TX user) has to touch fields
that are contained in many different cache lines.
The really critical thing is to shrink number of cache lines that are
used at RX softirq time : CPU handling softirqs for a device can receive
many frames per second for many sockets. If load is too big, we can drop
frames at NIC level. RPS or multiqueue cards can help, but better reduce
latency if possible.
This patch starts with UDP protocol, then additional patches will try to
reduce latencies of other ones as well.
At RX softirq time, fields of interest for UDP protocol are :
(not counting ones in inet struct for the lookup)
Read/Written:
sk_refcnt (atomic increment/decrement)
sk_rmem_alloc & sk_backlog.len (to check if there is room in queues)
sk_receive_queue
sk_backlog (if socket locked by user program)
sk_rxhash
sk_forward_alloc
sk_drops
Read only:
sk_rcvbuf (sk_rcvqueues_full())
sk_filter
sk_wq
sk_policy[0]
sk_flags
Additional notes :
- sk_backlog has one hole on 64bit arches. We can fill it to save 8
bytes.
- sk_backlog is used only if RX sofirq handler finds the socket while
locked by user.
- sk_rxhash is written only once per flow.
- sk_drops is written only if queues are full
Final layout :
[1] One section grouping all read/write fields, but placing rxhash and
sk_backlog at the end of this section.
[2] One section grouping all read fields in RX handler
(sk_filter, sk_rcv_buf, sk_wq)
[3] Section used by other paths
I'll post a patch on its own to put sk_refcnt at the end of struct
sock_common so that it shares same cache line than section [1]
New offsets on 64bit arch :
sizeof(struct sock)=0x268
offsetof(struct sock, sk_refcnt) =0x10
offsetof(struct sock, sk_lock) =0x48
offsetof(struct sock, sk_receive_queue)=0x68
offsetof(struct sock, sk_backlog)=0x80
offsetof(struct sock, sk_rmem_alloc)=0x80
offsetof(struct sock, sk_forward_alloc)=0x98
offsetof(struct sock, sk_rxhash)=0x9c
offsetof(struct sock, sk_rcvbuf)=0xa4
offsetof(struct sock, sk_drops) =0xa0
offsetof(struct sock, sk_filter)=0xa8
offsetof(struct sock, sk_wq)=0xb0
offsetof(struct sock, sk_policy)=0xd0
offsetof(struct sock, sk_flags) =0xe0
Instead of :
sizeof(struct sock)=0x270
offsetof(struct sock, sk_refcnt) =0x10
offsetof(struct sock, sk_lock) =0x50
offsetof(struct sock, sk_receive_queue)=0xc0
offsetof(struct sock, sk_backlog)=0x70
offsetof(struct sock, sk_rmem_alloc)=0xac
offsetof(struct sock, sk_forward_alloc)=0x10c
offsetof(struct sock, sk_rxhash)=0x128
offsetof(struct sock, sk_rcvbuf)=0x4c
offsetof(struct sock, sk_drops) =0x16c
offsetof(struct sock, sk_filter)=0x198
offsetof(struct sock, sk_wq)=0x88
offsetof(struct sock, sk_policy)=0x98
offsetof(struct sock, sk_flags) =0x130
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
UDP sockets refcount is usually 2, unless an incoming frame is going to
be queued in receive or backlog queue.
Using atomic_inc_not_zero_hint() permits to reduce latency, because
processor issues less memory transactions.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now vlan are lockless, we dont need special ndo_select_queue() logic.
dev_pick_tx() will do the multiqueue stuff on the real device transmit.
Suggested-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
vlan is a stacked device, like tunnels. We should use the lockless
mechanism we are using in tunnels and loopback.
This patch completely removes locking in TX path.
tx stat counters are added into existing percpu stat structure, renamed
from vlan_rx_stats to vlan_pcpu_stats.
Note : this partially reverts commit 2e59af3dcb (vlan: multiqueue vlan
device)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
macvlan is a stacked device, like tunnels. We should use the lockless
mechanism we are using in tunnels and loopback.
This patch completely removes locking in TX path.
tx stat counters are added into existing percpu stat structure, renamed
from rx_stats to pcpu_stats.
Note : this reverts commit 2c11455321 (macvlan: add multiqueue
capability)
Note : rx_errors converted to a 32bit counter, like tx_dropped, since
they dont need 64bit range.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Ben Greear <greearb@candelatech.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Version 4 of this patch.
Change notes:
1) Removed extra memset. Didn't think kcalloc added a GFP_ZERO the way kzalloc did :)
Summary:
It was shown to me recently that systems under high load were driven very deep
into swap when tcpdump was run. The reason this happened was because the
AF_PACKET protocol has a SET_RINGBUFFER socket option that allows the user space
application to specify how many entries an AF_PACKET socket will have and how
large each entry will be. It seems the default setting for tcpdump is to set
the ring buffer to 32 entries of 64 Kb each, which implies 32 order 5
allocation. Thats difficult under good circumstances, and horrid under memory
pressure.
I thought it would be good to make that a bit more usable. I was going to do a
simple conversion of the ring buffer from contigous pages to iovecs, but
unfortunately, the metadata which AF_PACKET places in these buffers can easily
span a page boundary, and given that these buffers get mapped into user space,
and the data layout doesn't easily allow for a change to padding between frames
to avoid that, a simple iovec change is just going to break user space ABI
consistency.
So I've done this, I've added a three tiered mechanism to the af_packet set_ring
socket option. It attempts to allocate memory in the following order:
1) Using __get_free_pages with GFP_NORETRY set, so as to fail quickly without
digging into swap
2) Using vmalloc
3) Using __get_free_pages with GFP_NORETRY clear, causing us to try as hard as
needed to get the memory
The effect is that we don't disturb the system as much when we're under load,
while still being able to conduct tcpdumps effectively.
Tested successfully by me.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Maciej Żenczykowski <zenczykowski@gmail.com>
Reported-by: Maciej Żenczykowski <zenczykowski@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Using %pV reduces the number of printk calls and
eliminates any possible message interleaving from
other printk calls.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The changed functions do not modify the NL messages and/or attributes
at all. They should use const (similar to strchr), so that callers
which have a const nlmsg/nlattr around can make use of them without
casting.
While at it, constify a data array.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Sending zero byte packets is not neccessarily an error (AF_INET accepts it,
too), so just apply a shortcut. This was discovered because of a non-working
software with WINE. See
http://bugs.winehq.org/show_bug.cgi?id=19397#c86http://thread.gmane.org/gmane.linux.irda.general/1643
for very detailed debugging information and a testcase. Kudos to Wolfgang for
those!
Reported-by: Wolfgang Schwotzer <wolfgang.schwotzer@gmx.net>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Tested-by: Mike Evans <mike.evans@cardolan.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
John Fastabend